


The Taboo Is In The Blood

by Ironkhaleesi



Series: Little Sister!Reader Incest - Marvel/Supernatural/Sherlock/Vikings/The Originals/Game of Thrones/Teen Wolf/King Arthur: Legend of the Sword [2]
Category: Supernatural
Genre: Angst, F/M, Incest, Multi, Reader Insert, SPN - Freeform, Sam Winchester fan fic, Sibling Incest, Supernatural - Freeform, Wincest - Freeform, dean fan fic, dean fan fiction, dean one shots, dean winchester fan fic, dean winchester fan fiction, dean winchester one shots, no wincest between brothers, sam fan fic, sam fan fiction, sam one shots, sam winchester fan fiction, sam winchester one shots, sister reader, sister winchester, spn fan fic, spn fan fiction, spn one shots, supernatural fan fic, supernatural fan fiction, supernatural one shots
Language: English
Status: Completed
Published: 2017-01-07
Updated: 2017-07-20
Packaged: 2018-09-15 11:18:05
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 5
Words: 9,812
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/9232508
Author URL: https://archiveofourown.org/users/Ironkhaleesi/pseuds/Ironkhaleesi
Summary: Growing up, it had been you and Sam against Dean and John. And then John died, Sam came home and suddenly it was the three of you against the world. What grew from that was a love and desire that none of you were willing to admit to - Sam and Dean had fallen in love with their little sister.





	1. Chapter 1

**Author's Note:**

> I'm posting this as a sort of prelude to a new series. I've never written Wincest before so I wanted to just throw this out there and see what you guys thought of it. If it goes well, I'll continue on with it :) So let me know what you think in the comments! You can even suggest what you'd like to see happen.

Being a Winchester was hard. Being a woman and being a Winchester was like walking across hot asphalt with glass in your feet. You were left with holes, scars and burns, while your dad and two older brothers stood at the side of the road saying you were a fucking idiot for even attempting it. 

Everything was harder. 

You worked harder. You played harder. You had more to prove. 

The older Sam got the more he tried to help rather than hinder you but John and Dean always stepped on your cape when you ran past. 

“Don’t be a hero, Y/N,” John always said. 

Dean always followed up with, “You’re smaller than us. Fragile. Don’t leave without one of us at your back.”

Realistically, you knew they were trying to protect you. You were Dean’s baby sister. John’s little girl. After Mary died you were the only girl in the family. 

You also liked to believe that their alpha male instincts took over and fried their brain cells. You half expected Dean to hit you over the head with a club and drag you off somewhere. 

Sam was easier to deal with. You were his baby sister too, and in the beginning, he followed in Dean and John’s treatment of you. Then he got older and realised the life he was living wasn’t the life he wanted. 

He realised he was only making your life harder too. So he helped you fight back. 

It never worked. The two youngest fighting against the two eldest but you and Sam bonded over the mutual enemy. The support brought the two of you together. 

He broke your heart the day he left. 

He wasn’t the same when he came back. 

After John died you felt … relieved. You’d never tell Sam or Dean that. You loved your father, you did, but after he died it was like an enormous weight was lifted from your shoulders.

Dean scaled it back. He stopped treating you like a helpless child and started treating you like the capable woman you were. 

You supposed it was because he realised it was just you and him left. Sam was there, of course, but it felt like he always had one foot out the door. Like the moment the Impala rolled to a stop, he’d jump out and you’d never see him again.

So you and Dean kept him on the road. And suddenly, just like you and Sam had bonded in your rebellion against your father, you and Dean bonded over the desperate need to keep Sam around. 

But every time you looked at him, all you could think was that he wasn’t your Sammy. He wasn’t the Sammy that watched dorky films and laughed at the bad CGI with you. He wasn’t the Sammy that squeezed your hand tight when the two of you went up against John. And he wasn’t the Sammy that cried when you begged him not to leave you for Stanford. 

He was just the Sam that left you.

As the years passed by, the three of you grew used to the different dynamic. You all realised that each one of you had changed since you were kids. You’d all changed since John died. 

You relearned each other’s bad habits. You relearned how each of you moved about the world until finally the three of you fell in sync in a way you never had as a child. 

That was another reason you were glad for John’s death. None of you had ever been as close as you were now. There had always been a clear cut hierarchy between the three of you and you’d always been on the bottom tier. But now, without John to enforce his way of life, the hierarchy had collapsed. 

Your strengths and weaknesses began to fit together perfectly until the three of you were a perfect puzzle. One of your strengths would hold up another’s weakness. And, in turn, they would do the same.

But nothing is truly perfect. With the new found love came a different kind of tension. 

The kind of tension that none of you were willing to admit to. 

Suddenly, Dean stopped sleeping around, and Sam stopped dreaming of the day he’d settle down with a wife.

Suddenly, you became caught in the middle of a silent war, and no one wanted to admit what they were fighting for. 

Suddenly, Sam and Dean’s touches lingered a little too long. They stared a little more often. 

You began making up excuses to wear their flannels, and they stopped correcting people when you were mistaken for one of their girlfriends. 

Of course, the three of you never talked about the changes. 

Winchesters never talked about feelings. Least of all feelings as taboo as what the three of you felt. 

No, the changes just happened. And the tension built. 

Sam and Dean fought more often because of the tension but they were also closer than they’d ever been. 

There was nothing like a mutual desire for their little sister to bring two brothers together. 

Often, you bitterly wondered what John would think if he could see his kids now. All grown up and resisting the urge to fuck one another. 

Sometimes, when the guilt got too much, you blamed him. Forcing three kids into a life of isolation. Never stopping long enough for them to make friends outside of their little trio. 

Even with the hierarchy, you’d always turned to your brothers for everything. Including discussions about sex. 

At the age of fifteen, Sam and Dean knew more about your confused sexual desires than anyone else. When the three of you grew up and became close, that didn’t change. 

Sam had experienced social life outside the trio, sure, but he always felt more comfortable talking to you and Dean about personal things than anyone else. 

You felt the most comfortable. You’d didn’t grow up with a mother figure, and John hated the idea of discussing sex with his daughter, so Sam and Dean had taken on that role.

Now … now, despite never having given in to the urges, Sam and Dean – theoretically – knew exactly how to make you cum. 

They knew what you liked in bed. What you didn’t. They knew all the things you wanted to try but wouldn’t because you couldn’t fathom putting that trust in a stranger. 

Because it was only strangers that you’d ever been with.

Dating wasn’t an option for any of you, not with how you felt. 

Sam’s only girlfriend had died, and after that, he couldn’t stand the thought of dating anyone while you were around. 

Dean had always ended up dumping his flings because none of them liked you (sometimes you thought they subconsciously knew Dean was comparing all of them to you).

And you … well, you’d had a boyfriend once. Then Dean put him in the hospital. He never admitted why but you all knew. He couldn’t watch another man shove his tongue down your throat when that’s exactly what Dean wanted to do himself. 

So, he got drunk and beat the guy up. After that, it was the unwritten rule. None of you were allowed to date. 

The odd one-night-stand here and there if you were separated from the brothers for a short period of time but mostly fooling around with other people just caused trouble. 

And yet, despite all the obvious signs, none of you were willing to admit it. 

No one wanted to admit that Sam and Dean were in love with their little sister.

**Notes for the Chapter:**

> I've got more fics at iavengesuperwholock.tumblr.com


	2. Chapter 2

**Summary for the Chapter:**

> Sam wakes up in the middle of the night with you next to him. He battles his shame even as he allows himself to touch you the way a brother should never touch his little sister.

It was your scent that woke him.

Sam had always been crazy about the way you smelled. It was something that was so unique to you and so sweet that it tugged at his heart every time you were near. 

He wanted to spend hours taking in his fill of you. Press his nose against your skin until he was so high on you he couldn’t move. 

But you were his little sister. That thought would bring everything to a grinding halt. Because brothers weren’t meant to think like that about their little sisters. 

But Sam did.

The guilt was enough to drag him to his knees. 

You were in bed asleep with your back to him. So close that he just had to slide his hand a few centre meters forward and he’d be touching the bare skin of your back where his shirt had bunched up around your waist. 

Normally, you slept on the fold-out couch in the motels while the brothers took the beds (they were too tall for the fold-outs). But it had jammed shut and it was too late to call someone in from the office to fix it.

Realistically, Sam knew you could have just slept on the couch the way it was. There were spare blankets and pillows in the cupboard. But Sam had jumped at the chance to have you sleep in his bed. 

Dean was already passed out, so there’d be no hard looks from him that said he knew exactly what Sam was doing. 

So, he’d told you to sleep in his bed and you’d accepted without hesitation. He knew you would. He knew your desires were just as wrong as his. As wrong as Dean’s. No words needed to be said for each of you to know how the others felt. 

He let his eyes rove down your back, illuminated by the moonlight coming in through the curtains, until they landed on your cotton underwear. 

You always wore bikini underwear – not something a brother should know but we’ve already established that the Winchester’s were a screwed up bunch. 

The curve of your ass and the way it seemed to burst out beneath your underwear was enough to make his palm itch.

Had you been any other woman, he would have given into the urge to touch you but you weren’t just any other woman. 

He wasn’t allowed to touch you like that. It was wrong … except … everyone who thought it was wrong wasn’t in the room just then. No one had to know. 

He could wake up in the morning and pretend it hadn’t happened. 

He held his breath and slid his hand the short distance across the sheets to reach you. His breath came out in a whoosh when his fingertips brushed against your skin and the nerves of his hand sparked to life. 

The moment that feeling hit him, he didn’t hesitate. His fingers ran over the soft skin that your underwear couldn’t covered. He pushed them down a little further to trace along the creases beneath your ass cheeks – stopping just as he hit the cotton that ran between your thighs. 

He wanted to squeeze your flesh but was worried he’d wake you. And he didn’t want to do that. Not because he thought you’d get upset and push him away but because he knew you wouldn’t.

Had you woken just then, he knew you’d allow him to keep going. You were the only one who was insane enough to fearlessly push the boundaries of what was going on between the three of you. 

He pressed his lips together and moved his hand away from the temptation of your ass to curve over your hip. 

Except, when he did that, the sparks fell away because your hip was covered with cotton. At least, that was the justification he gave himself as he let his hand slide under the fabric so there was nothing between the palm of his hand and your naked hip. 

He told himself that was as far as he would go. He would leave his hand there and that would be enough to satiate his urges. But even as he told himself that, his hand inched forward until his fingers curved over the front of your hipbone to brush against the edge of your pubic area and lower abdomen. 

He held his breath again as he pushed his hand down further. His pinky, ring finger and part of his middle finger slid beneath your underwear as he stroked his hand back and forth along the area where your lower abdomen met your pubic area. 

His breathing became heavier as his body came to life with the combination of guilt, shame and unadulterated desire for his little sister.

He shifted forward just enough to bury his nose in your hair and draw in the scent of your shampoo. 

You hummed in your sleep, shifted until your ass pressed against his crotch, and he froze. 

When he was sure you were still asleep, he squeezed his eyes shut and pressed his forehead against the back of your head as he brought his hand up to the dip of your waist.

God, he was a fucking creep. 

His little sister’s ass was pressed against his crotch and all he could think about was thrusting it against her. 

He didn’t realise he was squeezing your waist too tight until you stirred with a mumbled protest and opened your eyes. 

“Sammy?”

Two things happened then: his eyes snapped open as the sound of his name, a breathy sigh that fell from your lips, sent blood rushing beneath the waistband of his sweats; and he froze with the realisation that you were awake now and there was no pretending in the morning that none of this happened. 

“I didn’t mean to wake you.” It was all he could say. Because he couldn’t lay there in silence – with the way he’d squeezed you, there was no way you’d think he was asleep. 

But what else was he meant to say? 

You were silent for a heartbeat and the sound of Sam’s blood rushing in his ears was almost deafening.

“I don’t mind,” you whispered as you moved your hand up to cover his. He knew you weren’t talking about him waking you up. 

You threaded your fingers through his and guided it over the skin your stomach, slowly, giving him the chance to back out. 

You pushed his hand under the shirt you were wearing and knew where you were guiding him before the tips of his fingers even brushed against the underside of your breast.

Ever so slightly, you rolled your ass back against him and he breathed out a moan against the back of your head. 

With a bolstered confidence and renewed fervour, you pressed his hand firmly against your flesh and pushed his hand up until it cupped the underside of your breast. 

He gritted his teeth, mustered up the last remaining willpower he had and told you to stop just as the tip of his finger brushed against the edge of your nipple.

You dropped your hand from his but he didn’t bother moving his own hand from your breast. He didn’t have enough willpower for that.

“Sweetie,” he said, his voice sounding wrecked, even to him. “We can’t.”

“Why?” you said.

“You know why.”

You rolled your ass back against him again. He squeezed his eyes shut as his jaw ticked with the effort to do nothing. 

“No one has to know,” you said.

You were giving him permission. A chance to do something he’d been dreaming about doing for years. He wanted to take it and run. 

“I’ll know,” he ground out through clenched teeth. 

Your body stiffened for a moment before you rolled over to face him. His hand slid away from your breast as you did, brushed against the underside of the other one before curving over your ribs and resting in the middle of your back. 

His breath hitched when your eyes met his. There was a vulnerable innocence in them that made him think about all the times when you were little that you used to get scared and look up at him with big, innocent eyes.

He felt dirty. The protectiveness and love he’d felt for you back then had morphed into a sick desire that only grew stronger the more he tried to force it down. 

“Are you ashamed of me?” you said.

The words were a knife in his heart. He was meant to protect you; not make you feel shameful.

“I could never be ashamed of you,” he said. 

He was only ashamed of himself, and he let you see that in his eyes. Your eyes filled with unshed tears when you saw it. 

You moved forward and tucked your head under his chin. He rolled to his back so he could wrap his arms around your waist and you could throw your leg over his. 

You cuddled into his side like you used to when you were little and upset with Dean or John or both. 

Sam swallowed as tears filled his eyes.

**Notes for the Chapter:**

> I've got more fics at iavengesuperwholock.tumblr.com


	3. Chapter 3

**Summary for the Chapter:**

> After teasing Sam into an acceptance of his feelings for you, you go with Dean to the local bar. There, the two of you are almost caught red-handed pretending to be something neither of you was allowed to be.

Sam grunted when you took a running leap and jumped on him. You laughed and shifted until you were straddling his hips, your knees sinking into the mattress on either side of him. 

His mind immediately went back to the night before when your ass had been pressed into his crotch and he’d been fighting against everything that told him to pull your underwear to the side and sink himself into you. 

Now he was pressed up against a far more intimate part of your body. And with only your underwear and his sweats between you, there was no way you couldn’t feel him between your thighs. 

“You coming to the bar with us?” you said, seemingly oblivious to the nervous tick in Sam’s jaw. 

His fingers twisted in the sheets and his abdominal muscles tightened when your fingers rested against them. He suddenly wished he’d worn a shirt when he slept with you last night but somehow he didn’t think that would have made a difference. 

He swallowed. “Uh, no. I think … I’m just gonna catch some shut eye. You and Dean go.”

You smiled and rolled your eyes. “Come on, Sammy. You’ve been sleeping all day. Just come.”

As you said those last words, you began bouncing on your knees. A strangled sound fell from his lips as he tried to stifle his moan. His lifted his hands and wrapped them around your hips in a bruising grip to hold you still. 

It had felt far too much like you were doing something else. Sam’s willpower was good but when he knew that you wanted exactly what he was trying to avoid … it was becoming non-existent. 

You sank your teeth into your bottom lip with a knowing smile and glanced down to where your bodies were pressed together. He knew for a fact that you could feel him growing harder beneath you. 

You fell forward until your hands were bracing against his chest. “Dad’s not here anymore, Sam. And we’re not tied to any town. You don’t have to feel guilty for wanting this.” You rolled your hips against him. He sucked in a breath and his top lip snarled. You smiled. “For wanting me.”

Sam let out a soft moan when you rolled your hips against him again. “I’m your big brother, Y/N. So is Dean.”

You let out a sigh of pleasure as you rolled against him again and straightened back up. “I know. I can’t think of any other two people I’d want to touch me like this. Can you?”

Sam didn’t answer. He simply clenched his teeth and squeezed your hips tighter when you began a steady rhythm of rubbing yourself up and down his covered length. 

“Is that what you want, Sammy?” you said, your voice coming out breathy. “Do you want me to find someone else …” you let out a soft moan, “to satisfy me like this?”

His brow furrowed and he squeezed his eyes shut as he let his head fall back into the pillows. “No,” he ground out through clenched teeth.

He knew this was wrong, on so many levels, he knew it. But the thought of you doing this to another man – the thought of anyone else touching you the way he was – filled him with rage and nausea. 

You fell forward on your hands again, your thrusts ceasing, and Sam opened his eyes to look up at you. He wished you weren’t the most beautiful thing he’d ever seen. He wished he didn’t crave the feel of your body every second of every day. He wished he didn’t have the urge to fuck you until it hurt.

He wished he wasn’t in love with his baby sister. 

But he was, and there was no turning back now. 

You gave him a gentle smile when you saw the acceptance in his eyes.

The bathroom door opened then and Dean walked out in just a pair of jeans with steam billowing behind him. You straightened, looking over your shoulder at him with an innocent smile and Sam’s hands flew up to rest under his head. 

He knew that Dean would know what had been going on. He even knew that Dean wouldn’t shame him for it. But the guilt was so prevalent in Sam that it was automatic instinct to make himself look innocent.

Dean looked between the two of you as if seeing his brother and sister in such an intimate position was the most natural thing in the world.

He sighed when he took a better look at you. “Sweetheart, you said you were getting dressed.”

You grinned. “I am dressed.”

Dean rolled his eyes and growled, “Like hell you are,” as he moved forward to wrap an arm around your waist and hoist you off Sam and the bed.

Sam swallowed and sat up immediately, using a pillow to cover his erection. 

“You’re not going to the bar just wearing my flannel,” Dean said. 

You pouted and Sam felt his lips curl up into a soft smile as he watched the two of you bicker about what you were wearing. He knew that you could easily put your foot down and wear whatever the hell you wanted. But he also knew that you loved that Dean got possessive when he knew you were going to be around a bunch of drunk, horny guys. 

Watching the two of you bicker was something that had always brought Sam peace. If the two of you were bickering about menial crap, then it meant everything was okay. 

Despite the fact he and Dean were in love with their baby sister and wanted to touch you in the most intimate of ways … everything was okay. The world wasn’t going to burn to the ground. 

****

Dean grumbled under his breath as he followed you into the bar. He’d argued against you wearing his flannel to the bar, and whilst you’d obeyed him in that regard, he sure as hell didn’t get what he wanted. 

You were in a sun dress that hit you way higher up on the thighs than his flannel did. It gave shape to your body and every time you moved the back of it bounced up to just below your ass. 

He was not happy. He was angry and horny and feeling possessive as all hell when male eyes started turning your way.

You were oblivious to the attention. It calmed Dean a little to know that he and Sam were the only men you ever paid attention to but he was still tense with the anticipation of a fight when you found a table and bounded ahead of him to grab it.

He made eye contact with every man he passed that looked at you. He’d narrow his eyes and his jaw would tick, a silent message that none of them would be welcome at your table. 

You climbed up onto your bar stool and smiled over at him. He felt his face soften with affection when you did and he didn’t give a damn who saw it. 

He wasn’t like Sam. He knew his little brother was filled with guilt over his feelings for you but those days were over for Dean. His entire childhood had been spent in guilt over his feelings, that why he’d been so hard on you.

You’d always thought that Dean’s feelings hadn’t developed until the three of you were adults and John was long gone but that was only the case for Sam. Dean couldn’t even remember when he’d started developing feelings for you. They’d just always been there.

They were innocent when he was a kid. They just showed themselves as over-protectiveness. But then he hit his teenage years and the sexual feelings began developing. 

He still remembered how sick he felt. How guilty. He imagined it was how Sam felt now. But after John died and Sam began settling back in with the two of you – after he began noticing that Sam felt the same way – he stopped feeling guilty about it.

The only reason he didn’t talk about it or pursue those feelings was because he was trying to protect you. He knew if anyone who knew the three of you – any hunters or any of your friends – found out about what was going on … well, Dean had a thick skin but you’d spent your entire life fighting against him and John for the right to just be who you were. 

He wasn’t about to let anyone else make you do that ever again. 

“So, how drunk are we getting?” you said when Dean hoisted himself into the seat beside you. He found the way you kicked your legs endearing. “Like, giggly drunk, dancing drunk, or you-kiss-me-and-pretend-it-never-happened-in-the-morning drunk?”

Dean looked at you with a cocked brow. Your eyes lit up with the laugh you were stifling. 

He chuffed. “I’m not Sammy, sweetheart. You can’t make me blush.”

You smiled. “Bet I can.”

You slid your hand onto his upper thigh and leaned into him until your breast brushed against his arm.

He looked down at you, his eyes dropping to your cleavage for a moment because that’s what you wanted and he’d never been able to say ‘no’ to his baby sister since John died. 

His eyes swept up your neck and lingered on your lips. They parted slightly as your tongue peeked out to wet them. They curled up at the corners and he realised it was because his own lips had parted in response. 

Finally, he moved his eyes up to connect with yours. There was mischief in them. And lust. He knew how horny you must have been. 

The unspoken rule was that the three of you could have one night stands if the other two were out of town but Dean hadn’t flirted – let alone touched – another woman in years. He was positive you and Sam were the same. And, if he was being honest, he didn’t want that unspoken rule to be a rule anymore. 

As much as he knew he shouldn’t have you the way he wanted you, he’d be damned if another man ever touched you – whether he and Sam were out of town or not.

So, with the three of you practicing celibacy – though Dean knew his hand and your vibrator was getting a good workout – the sexual tension had been building. He only had to look at Sam before he left the motel to know that even he was on the precipice of breaking.

It was only a matter of time before the dam broke and the brothers had you confined to the bed for a week straight, or until they ran out of steam – whatever came first. 

When that happened – when the three of you took that final step – everything would be different. The tension would be gone, and, Dean was sure, Sam’s guilt would finally whither. All he needed to do was finally realise how right you were for the both of them. 

That you were the only one for them. That you had always been the only one.

And as Dean looked into your hooded eyes, he wondered if that night would be the night that he finally took that extra step with you. 

“Hi. Can I take your drink order?”

You and Dean dragged your eyes away from each other in a daze and stared at the waitress. 

“Huh?” Dean said.

The waitress had a knowing smile as she looked at the two of you. She chuckled when you both gave her a confused look. “Well, you two are adorable as all hell. So wrapped up in each other you don’t even know what’s going on around ya.”

“Well, what can I say?” Dean said as he turned his eyes back to you. He slid his rough hand onto your bare thigh, just where the hem of your dress stopped. “There’s nothing I’d rather be looking at.”

You tried to stifle your smile as you looked back at him but you knew it reached your eyes.

“Just two beers, thanks,” you said to the waitress without looking at her. You shook your head at Dean when she left. “You’re such a sap.”

He smiled back and shrugged as he let his hand slide from your thigh and back to the table. You moved your own back into your lap as well. “You’re the one who always wants to play along when people mistake us for a couple.”

You tilted your head in thought when his attention was drawn to the band that had started setting up on stage.

“Do you think it’s a mistake that people think that?” you said. 

Your voice had been so soft that you thought he might not have heard but then he looked at you with gentle eyes and shook his head.

“No, I don’t think that,” he said.

The night seemed to go on forever. By midnight, the two of you were drunk and leaning against each other. You whispered jokes and laughed amongst yourselves. It felt like you were the only people in the bar – maybe even the whole world. 

The touching was so casual and affectionate that no one in the bar could possibly think you were siblings. 

More than once, Dean had pressed a kiss to your face, each one landing closer and closer to your lips. Just as you kept squeezing his thigh – your hand landing higher and higher each time. 

His hand threaded through your hair and slid down your back. It glanced over your hip and ass as he pulled back to get the waitresses attention again – laughter still lighting up his eyes from the story you’d just told him. 

Before he could even put his hand up, the two of you were joined by a man. The moment you saw who he was, your mood soured and Dean’s smile dropped so his face was blank. 

The two of you shifted away from each other and Dean tried to subtly move his hand from your ass to the table.

“Hey, Dirk,” Dean said. 

Dirk was an old hunting buddy of John’s. That was the only reason he still acted friendly with you and the boys despite having been punched by all three of you.

He was far too hands-y and lewd towards you. Had been since you hit puberty. Not to mention misogynistic. 

“How’s it going, Dean?” Dirk said with a smile that sent shivers down your spine. They weren’t the kind of shivers that Sam and Dean gave you – the complete opposite, in fact.

You slid off of your stool immediately. You made no secret that you hated the man and didn’t want to be anywhere near him. In fact, you were sure that he contacted you guys sometimes just because he knew you were disgusted by him.

Your movement drew his attention because Dean looked to you the moment you stood.

“Y/N?” Dirk said. “Didn’t see you there. You’re looking mighty pretty in that dress, little lady. You should be dressing like that more often.”

“Hey!” Dean growled in warning.

What Dirk had said didn’t seem all that harmful but that was the problem. It was less what he said and more the intentions and implications behind it. 

When you were younger, Sam, Dean and John had never been able to figure out why you were always creeped out by the man. To them, what Dirk said never seemed that harmful. Of course, they didn’t like him complimenting you because you were related to them but ultimately he seemed harmless. 

But then John died and Dirk’s fear fell away. You guess he thought that your brothers wouldn’t have minded him trying to cop a feel of their little sister. Of course, you’d been the one to put the fear of God back into the man. When Sam found out, he got another good punch. But when Dean found out … you’d never seen a man’s face look so close to pulp before.

But that had been years ago and it seemed as though Dirk always came back like a cockroach. Only he was far more careful about what he did and said.

“Eat a dick, Dirk,” you said, then you headed towards the bar exit. 

You wanted to get away from the man, sure, but fear is what drove your legs to move fast. Because Dirk didn’t come from the direction of the bar entrance. He approached the two of you from the back, which meant he’d been in the bar long enough to grab a table and settle in for a few drinks. 

It meant that he could have been watching the two of you the entire time.

You burst through the door of the bar and headed straight for the Impala. You heard Dean calling your name but you didn’t stop until you reached the passenger side and his hand wrapped around your arm.

You turned and leaned back against the door, swallowing once before looking up at him. His eyes were blown with adrenaline and he seemed to be catching his breath. A glance at his split knuckles proved your suspicions.

He’d laid Dirk out. Again.

You shook your head and looked back up at him. “You shouldn’t have hit him, Dean.”

He frowned. “Why not? Not like I haven’t done it before.”

“You had a good reason before.”

“And this wasn’t good enough?” he growled. He gestured towards the bar entrance. “That guy's a creep. You know what he meant when he said that.”

You took a deep breath and scratched at your forehead. “But no one else does, Dean.”

Dean gave you another look of confusion. “What? You think he’s gonna start telling people I knocked him out for no reason?”

You shrugged. “Maybe. Or maybe he’s going to start telling people that he saw something he wasn’t meant to and that’s why you clocked him. We have no idea how long he was in there for. He could have been watching us the entire time and – and … you weren’t exactly treating me like I was your little sister in there, Dean.”

“Hey, calm down, sweetheart,” Dean said gently as he lifted his hands to your shoulders. “It’s gonna be okay. I promise. Even if he did see, even if he tells people, who’s going to believe him? Everyone knows he’s a creep, Y/N.”

“But what if –”

“Screw ‘what if’s’,” Dean growled as he moved his hands up to cup your face. He ducked his head down so it was level with yours. “Screw Dirk. Screw everyone who isn’t you, me and Sammy. Us? This? No one is going to take that away. I’d die before I let that happen.”

Your eyes welled up and all Dean wanted to do was take you far away from the bar. Far away from America where too many people stood in the way of what he wanted.

“Dean …” you said softly as you gave him a sad look. 

“Baby, I’m in love with you. I have been for as long as I can remember. I don’t care what happens to us. So long as you and Sammy are by my side, bring it on. But don’t push me away now. You’ve spent so long trying to get me and Sammy to come to our senses, don’t stop now.”

You gave him a sad smile and reached your hands up to wrap around his thick wrists. “I could never push you away, Dean.”

His shoulders sagged in relief and he let his forehead fall against yours. 

Your noses brushed. He rubbed his against yours a little more forcefully. Then his nose was brushing against your cheek as his head tilted. Your lips brushed together and then the bar door slammed open and you jerked back from him.

He sighed and pulled back as he let his hands drop to smooth down your arms. “Just a drunk couple,” Dean said as he glanced over the Impala to the bar entrance. 

He looked back down at you. Your arms were wrapped around yourself and you were staring at his chest.

“We should get back to the motel,” you said. “Sam will start worrying soon.”

You both knew that Sam wouldn’t start worrying until the sun was well and truly up. But Dean could see that you were still shook from the possibility of having been caught, so he let you call the shots. 

He nodded and glanced up again when he heard the drunk couple laugh amongst themselves. They were sharing stolen kisses as they leaned into each other and giggled at the rest of the world. It was with sadness that he realised, had things gone right that night, that happy, drunk couple could have been you and him.

How cruel must the universe be to put Dean’s perfect woman inside his little sister.

**Notes for the Chapter:**

> I've got more fics at iavengesuperwholock.tumblr.com


	4. Chapter 4

**Summary for the Chapter:**

> After weeks of avoiding the brothers, the tension between you and Dean snaps.

You and Dean lay in his bed, facing one another. It was the middle of the night and the bunker was quiet. You hadn’t bothered to come up with an excuse for crawling into his bed. You were both far past that point by now. 

It had been weeks since the two of you were almost caught at the bar. You’d been avoiding your brothers like the plague ever since. Especially Dean. It hurt but you had a lot to think about. 

Your hand sat on the bed between you, right next to Dean’s. So close you could feel each other’s energy. You both stared at them. 

“What if Sam’s right?” you said. You curled your pinkie into the bed, fighting the urge to slide your hand across those few millimetres and touch him. “What if we’re wrong to feel this?”

“Sam’s just feeling guilty,” Dean said, his eyes steady on your hand. He wanted to make the first move, to cross that threshold, but he knew Dirk had shaken you. You needed to make your own choice right now. 

“Don’t you?”

Dean looked at you. “No. I haven’t for a long time.”

You lifted your eyes to his. “Why not?”

“Because I love you.”

“But that’s wrong, Dean.”

“I don’t give a damn.”

You dropped your gaze once more and pulled your hand back towards your chest and away from Dean. He wasn’t having that. 

Yes, it was your choice to make, but ultimately, there was only one choice Dean would accept. 

He shifted forward and gathered you up in his arms. You nuzzled into him, much to his relief, and he kissed the top of your head before pressing his forehead to yours. 

“Yes. You’re my baby sister,” he said. “And yes, what we’re feeling is 50 shades of screwed up. But after everything we’ve done for this world and the hypocrites that live on it, we deserve this. They owe us this.”

He rubbed his nose against yours and pulled you in closer. His attempt at coaxing you into a kiss. After all those long years and all those close calls, it was driving him insane not to kiss you just then. 

“Dean …”

“We both want this, baby,” Dean whispered. “No one ever has to know. It’ll be our secret.”

“What about Sammy?”

Dean’s hand began to rub up and down your back, curving over your ass every so often as he felt your will begin to crumble. 

“He’ll come around,” Dean said. “I don’t mind sharing. Long as it’s just Sam I’m sharing you with.”

You’d run out of excuses, Dean could feel it. You began relaxing into him and Dean brushed his nose against yours again. Then his lips. He brought his hand up and cupped the side of your neck. Your lips parted and the anticipation grew. 

This was it. This was when the two of you would finally cross that forbidden line. 

Your lips meshed together, his tongue slid against yours. And everything exploded. 

He rolled you to your back, his body crushed yours into the mattress as he kissed you like it was the last kiss he would ever have. 

He pushed your thighs apart and you moaned as he settled between them, the weight of his hips against your core brought fire to the surface of your skin. 

He wore nothing but sweatpants and you were just in his shirt and a pair of underwear. You could feel him nestled against you. Lengthening and hardening. 

He broke away and moved his lips down to your neck. Biting and licking at whatever patch of skin he could get his mouth on. 

“I’ve waited so long for this,” he groaned. “For you.”

He pulled his knees underneath him and lifted your hips so your ass rested on his thighs. He sat up and moved his hands to your underwear, telling you to pull your shirt off as he yanked them over your hips.

You did as he asked, and lifted your legs so he could slide your underwear off as well. 

The moment you were naked and back in position, he slowed down and stared at your body. He ran his large, rough hands over your hips, your stomach. Caressed every part of you but the parts you wanted him to touch the most. 

He seemed in a daze. Like he was in awe of how you felt against his skin. You squirmed beneath his slow strokes, but he was intent on taking his time. 

By the time his hands wrapped around your breasts, they were so tight and full with arousal that your back bowed off the bed and you ground your core down onto him as a needy moan fell from your lips. 

He leant down briefly and sucked at them in an effort to ease the ache. When he sat back up, his hands slid down to the place you wanted them the most. 

You let out a shaky breath as he rubbed his thumbs over your outer lips, spreading them open for his viewing. He was mesmerised, and you’d never felt more desired than you did that second. 

Your teeth sank into your lower lip when he dipped his thumb into your juices and slid it up to circle your clit. A low groan vibrated up your throat as you rolled your hips against his hand. 

“You’re so beautiful,” he said. Though he sounded like he was saying it more to himself. Like he still couldn’t believe he had you laid out in front of him like this. 

“Please,” you whined. 

He looked up at you, and whatever he saw in your face kicked him into action. He kept his thumb at your clit, but slid two fingers of his other hand into you and curled them up into your g-spot. 

Your head pushed back into the pillows and you reached down to wrap your hands around his wrists. 

“Fuck, Dean,” you moaned. 

He smiled at your impatience. “Not keen on a little foreplay right now, baby?”

You wrapped your hands higher up his arms and he braced himself as you used that hold to pull yourself up into his lap. 

You groaned and rolled your hips as his fingers pressed deeper into you. 

“You mean you want to wait to feel me wrapped around you?” you breathed against his mouth as you fucked his hand. He let out a desperate sound. “You wanna wait to fuck me so hard I scream your name?”

He groaned. “God, no.”

He didn’t even manage to get his sweatpants all the way off before he was buried inside you. 

You both moaned obscenities against each other’s mouths as you bounced in his lap. He slapped your ass and you bit his lip. He called you his dirty little girl and you demanded he fucked you harder. 

Years upon years of built up sexual tension broke in that moment, and nothing could have torn the two of you apart. 

You were both so caught up in one another, that neither of you realised Dean’s door was still ajar. Enough so, that on his way back from the kitchen, Sam got an eye full of the two of you. 

He stood there, mouth hanging open, as he watched the two of you go at it. There was a desperation between the two of you. Like you were both terrified this might be the last time you could ever be together. 

Your bodies glistened with sweat, and Dean left bruises from the grip he had on your ass and hips. You pulled at his hair and scratched his shoulders. Your mouths were latched together, only breaking apart to moan and say the filthiest things that Sam had ever heard.

He tried to be disgusted. Tried to tell himself that this was wrong. But much like that moment he shared with you in the motel, he couldn’t bring forth those feelings. All he could do was imagine himself in there with you.

**Notes for the Chapter:**

> I've got more fics at iavengesuperwholock.tumblr.com


	5. Chapter 5

**Summary for the Chapter:**

> The final chapter where Sam finally comes to terms with his feelings. He gets drunk and makes a pass at you, but when you reluctantly turn him down, you're sure this is it for the two of you - he's going to decide not to pursue his feelings. But he surprises you and Dean the next morning.

Sam lived every day of his life believing that fucking his little sister would be the worst thing he could ever do – and he’d done some shit in his day. Even if he could look past the fact he was your older brother – something he had actually accomplished on numerous occasions; occasions often followed up with guilt – he still knew, deep down, he was no good for you. His baby sister deserved better than anything he could ever offer you.

And then he got drunk in some bar one night, and all of that went to crap. 

He hadn’t planned on it – not being the drinker that Dean was – but seeing you and his brother flirt all night drove him to the bottom of a whiskey bottle. And yet, he couldn’t drink away the image that was burned in his mind.

The image of Dean fucking you.

In fact, the drunker Sam got, the more he saw his own face superimposed over Dean’s in his mental image. And then he was the one flirting with you as Dean sat back and watched with caution. 

It wasn’t until Sam had you up in the middle of the dance floor, grinding against your ass and ghosting his lips over your neck, that Dean intervened. 

“Alright, Sammy,” Dean said as he pulled you away from your intoxicated brother. “We gotta move this somewhere more private.”

Dean looked around the bar as he spoke. The lights were dim and the music was loud, but his run in with Dirk a few months back had put him on edge when it came to PDA. 

Sam was more than happy to follow Dean as he lead you out of the bar. You barely made it back to the Impala when Sam was pushing you back against it and meshing his lips to yours.

It wasn’t the sweet, affectionate first kiss that you’d shared with Dean. This was Sam – it was desperate, messy and guilt-ridden. But you took what you could get. You would settle for drunk Sam because it was the only Sam you could get. 

You loved Dean, with everything you had, but you loved Sam too. You needed them both. One wasn’t enough to fill up the hole in your heart. 

He tried to tear open your flannel but only got a few buttons undone before his mouth was on your chest. Dean kept watch, though the Impala was in the darkest part of the lot, so he didn’t seem too concerned. 

Sam slurred something out that no one caught as he stumbled back and tried to pull open his belt buckle. It was then that you realised you couldn’t do this. 

He struggled with his belt, confused in his drunken state about how the thing worked. 

You could settle for drunk Sam. But sober Sam could never settle for you, and that’s who drunk Sam would become in the morning. 

“Stop, Sam,” you said. Your voice was barely above a whisper, but both your brothers heard you. You swallowed as you pulled your flannel closed. 

Sam swayed on his feet, his fingers still caught in his belt as he stared at you. 

“We’re going back to the motel. And you’re going to sleep.” You folded your arms and Dean moved closer. “This isn’t happening.”

Sam’s brow furrowed and he swayed some more when he tried to take a step forward. “What? But …” He didn’t even know what he wanted to say.

“You’re drunk, Sam,” you said. “And I’m … I wouldn’t be able to face you tomorrow if we did this. I couldn’t bear to watch you regret this. To watch you hate me for letting you do it.”

All Sam could do was stand there with that dumb, drunk look on his face. You knew he wouldn’t remember this in the morning. 

You looked at Dean. His face was patient and understanding. And as far from drunk as you needed him to be in that moment. You wished it was that easy with Sam, but you also knew that if it was … then he wouldn’t be the Sam you loved. 

“Takes us back? Please?” you said. 

Dean pressed his lips together in a sad smile. He knew how hard this was for you. “’Course, baby.”

****

You were grateful when you woke up in the morning to find Sam already in the shower. The longer it took for the two of you to face each other, the better. Dean was silent for the most part as you pushed your breakfast around on the plate with your fork. 

He tried to cheer you up – make some sort of conversation – but when he only got one-word answers and grunts, he gave up and let you be. Sometimes silent support was what you needed most. 

But all the support in the world didn’t prepare you for the moment Sam stepped out of that bathroom with just a towel wrapped around his waist. 

You stood from your chair when he walked towards the table.

“Hi,” you said.

“Hey,” he said, and you felt like you were in some stupid rom-com.

You swallowed and crossed your arms over your chest, suddenly conscious that you were wearing Dean’s flannel and nothing else.

“How do you feel?” you said. 

He shrugged. “Like I was hit by a truck last night.”

Neither of you laughed, and all you could wonder was whether or not he remembered what happened. You almost asked him, but forgetting it ever happened was the best thing Sam could do. The last thing you wanted was for him to feel ashamed. 

You went to turn away, but what he said next stopped you.

“I could never hate you,” he said. He stared down at you with those infamous puppy dog eyes. “But I’m glad you stopped me last night.”

The words pierced your heart and the floor fell out from under you. And you realised there was something worse than Sam remembering what happened – Sam rejecting you. Only this time it would be concrete. You could feel it. 

Your eyes welled up. His brow furrowed and his lips parted as he watched you do everything in your power not to fall apart. 

“Sam,” Dean said in warning as he stood from the table. His face was hard, his body tense. He expected about as much as you did, and he wasn’t about to stand by and watch Sam break your heart.

“It’s not like that,” Sam said. “I’m glad because … I want to be sober during our first time together.”

You could have sworn that your heart stopped for a second. You could practically feel Dean freeze behind you. Sam moved closer until you could feel the heat radiating from his body. He cupped your face in his hands.

“I regret a lot of things in my life,” he said. “But I will never regret you.”

He kissed you then, and it felt a lot more like the first kiss he’d been hoping for. It washed away the one from last night, and you were more than happy to return it. 

He was calm, now. More sure of himself and what he wanted. There was no guilt in this kiss, no desperation. He knew what he wanted and he was done feeling guilty for it. 

You were so entranced by the moment that you hadn’t noticed he’d unbuttoned Dean’s flannel until he pushed it off your shoulders and down your arms. It fell to the ground as Sam pulled back to look at you. 

His hands rested just above your elbows as his eyes drifted over your body. It wasn’t the first time he’d seen you naked – life on the road demolished all modesty between the three of you – but it was the first time he got to do something about you being naked. 

He seemed like he didn’t know where to start – like a kid in an amusement park. 

Then he remembered that Dean was still in the room. He looked at his brother over your head. “Wanna take the lead?” Sam said. 

Goosebumps rose along your arms when Dean’s rough hands slid onto your waist in answer. You tilted your head when his lips and tongue met your neck. Your eyes closed and your mouth fell open. 

Dean’s hands slid over your ribs and moved up to cup your breasts. Then Sam’s mouth was on your abdomen and you opened your eyes to find him on his knees in front of you.

His hands tickled over your thighs, played against the creases beneath your ass cheeks until you were restless between him and Dean. He left hickeys along your stomach as he trailed his hand down to one of your knees. He pulled it up over his shoulder, and your head fell back when his mouth drifted down between your thighs.

You moaned and slid one hand up to tangle in Dean’s hair as the other raked through Sam’s. 

Sam groaned at the taste of you and Dean’s mouth was at your ear, whispering the most sinful things to you as his hands continued to work on your breasts. 

“You like the way Sammy’s tongue feels, baby?” he said.

“Yes,” you breathed.

You rolled your hips against Sam’s mouth. He growled and pulled your other knee up so only he and Dean were supporting you. He pressed his tongue harder against you, sliding it through your folds before he focused on your clit. 

One hand gripped your thigh and the other moved up so he could play his fingers against your opening. You sucked in a sharp breath when he slid two of them in and curled them against your g-spot. 

Dean moved one arm down to wrap around your waist, the other one he moved up between your breasts to grip your shoulder, effectively holding you still and forcing you down on Sam’s mouth at the same time.

You groaned when Sam’s tight hold on your thigh stopped you from rolling your hips, and you were forced to stay still and endure the intense pleasure.

“Tell him how much you love his mouth on your pussy,” Dean growled in your ear.

You whined and tightened your fingers in Dean’s hair.

“Sammy,” you moaned, “I love the way your mouth feels on my pussy.”

Sam growled against your flesh and your head fell back again.

“Look at him,” Dean growled. “Beg him to make you cum.”

You whined again and did what you were told. “Please, Sammy. I wanna cum.”

Sam’s eyes flicked up to yours. He worked his tongue and fingers faster, eager to push you over that edge. You breathing picked up. Your moans started coming at a higher pitch as the knot in your stomach tightened.

“You gonna cum all over your brother’s mouth, huh?” Dean said.

That did it. Sam and Dean’s grip on you turned bruising as they tried to hold you still. You jerked in their arms, your thighs tightened around Sam’s head as your orgasm crashed into you. 

You were begging by the end of it, but you had no idea what you were begging for, and it wasn’t until then that Sam pulled back and lowered your feet back to the floor. 

He stood and took you into his arms when Dean let you go. He pressed his lips to the top of your head and squeezed you to him for a moment before he looked up at his brother.

“Dean …”

Dean nodded. “I know. Text me when you guys are done.”

Sam was grateful for Dean’s understanding. As much as he didn’t mind sharing you with his brother, Sam wanted you all to himself the first time, just the way Dean had it. 

Dean pressed a kiss to your temple before he left the motel room. Sam scooped you up in his arms and took you to the bed. He pulled the towel from his body before he settled between your thighs. 

He took a moment to study your face. Your eyes were still a little dazed, your lips parted in anticipation and your body was lax and waiting. 

He pressed a kiss to your lips, then stroked a thumb over your cheek. 

“I love you,” he said. And he sank himself into you before you got a chance to reply. 

He’d been to heaven before, and this moment was far better than anything he’d ever experienced up there. 

Your nails dug into his back as he rolled his hips against you. He kissed you between the moans and grunts that were torn from his throat. 

Making love to his sister shouldn’t have felt this amazing, but Sam was beyond caring at this point. You were exactly what he wanted – what he needed – in this life, he was over trying to justify that to himself. 

No one had to know he found his deepest pleasure inside of you. And as long as he wasn’t hurting anyone, Sam was willing to come to terms with it himself. Hearing you cry out his name in pleasure made it easier for him to accept. 

Sam and Dean Winchester were in love with their baby sister, and nothing would stop them from having you.

**Notes for the Chapter:**

> I've got more fics at iavengesuperwholock.tumblr.com


End file.
